@book{1531,
	author = {Cuanalo de la Cerda, Heriberto E. and Ojeda Trejo, Enrique.},
	title = {Provincias regiones y subregiones terrestres de México.},
	publisher = {Colegio de Postgraduados,},
	year = {1989.},
	address = {Montecillo, Méx. :}
}